16 research outputs found
Spread of artemisinin resistance in Plasmodium falciparum malaria.
BACKGROUND: Artemisinin resistance in Plasmodium falciparum has emerged in Southeast Asia and now poses a threat to the control and elimination of malaria. Mapping the geographic extent of resistance is essential for planning containment and elimination strategies. METHODS: Between May 2011 and April 2013, we enrolled 1241 adults and children with acute, uncomplicated falciparum malaria in an open-label trial at 15 sites in 10 countries (7 in Asia and 3 in Africa). Patients received artesunate, administered orally at a daily dose of either 2 mg per kilogram of body weight per day or 4 mg per kilogram, for 3 days, followed by a standard 3-day course of artemisinin-based combination therapy. Parasite counts in peripheral-blood samples were measured every 6 hours, and the parasite clearance half-lives were determined. RESULTS: The median parasite clearance half-lives ranged from 1.9 hours in the Democratic Republic of Congo to 7.0 hours at the Thailand-Cambodia border. Slowly clearing infections (parasite clearance half-life >5 hours), strongly associated with single point mutations in the "propeller" region of the P. falciparum kelch protein gene on chromosome 13 (kelch13), were detected throughout mainland Southeast Asia from southern Vietnam to central Myanmar. The incidence of pretreatment and post-treatment gametocytemia was higher among patients with slow parasite clearance, suggesting greater potential for transmission. In western Cambodia, where artemisinin-based combination therapies are failing, the 6-day course of antimalarial therapy was associated with a cure rate of 97.7% (95% confidence interval, 90.9 to 99.4) at 42 days. CONCLUSIONS: Artemisinin resistance to P. falciparum, which is now prevalent across mainland Southeast Asia, is associated with mutations in kelch13. Prolonged courses of artemisinin-based combination therapies are currently efficacious in areas where standard 3-day treatments are failing. (Funded by the U.K. Department of International Development and others; ClinicalTrials.gov number, NCT01350856.)
Pf7: an open dataset of Plasmodium falciparum genome variation in 20,000 worldwide samples
We describe the MalariaGEN Pf7 data resource, the seventh release of Plasmodium falciparum genome variation data from the MalariaGEN network. It comprises over 20,000 samples from 82 partner studies in 33 countries, including several malaria endemic regions that were previously underrepresented. For the first time we include dried blood spot samples that were sequenced after selective whole genome amplification, necessitating new methods to genotype copy number variations. We identify a large number of newly emerging crt mutations in parts of Southeast Asia, and show examples of heterogeneities in patterns of drug resistance within Africa and within the Indian subcontinent. We describe the profile of variations in the C-terminal of the csp gene and relate this to the sequence used in the RTS,S and R21 malaria vaccines. Pf7 provides high-quality data on genotype calls for 6 million SNPs and short indels, analysis of large deletions that cause failure of rapid diagnostic tests, and systematic characterisation of six major drug resistance loci, all of which can be freely downloaded from the MalariaGEN website
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Understanding the Motivations of the Tourist Audience at Museum Victoria
This project sought to develop an understanding of the tourist audiences in the city of Melbourne, Australia--specifically at Melbourne Museum and Immigration Museum. Data was collected on-site and off-site from 400 individuals. Analysis revealed that tourists primarily use word of mouth and online resources to obtain information about city attractions. Using this data, our team developed recommendations to assist Museum Victoria in better marketing its products and exhibitions to Melbourne tourists
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Responsiveness of 8 Patient-Reported Outcomes Measurement Information System (PROMIS) measures in a large, community-based cancer study cohort.
BackgroundThe Patient-Reported Outcomes Measurement Information System (PROMIS) was a National Institutes of Health-funded initiative to develop measures of symptoms and function. Responsiveness is the degree to which a measure can detect underlying changes over time. The objective of the current study was to document the responsiveness of 8 PROMIS measures in a large, population-based cancer cohort.MethodsThe Measuring Your Health study recruited 2968 patients who were diagnosed with 1 of 7 cancers between 2010 and 2012 through 4 Surveillance, Epidemiology, and End Results registries. Participants completed a baseline survey (6-13 months after diagnosis) and a 6-month follow-up survey. Changes in 8 PROMIS scores were compared with global ratings of transition, changes in performance status, and clinical events.ResultsMeasures were responsive to 6-month declines and improvements in performance status with small to large effect sizes (ES) (Cohen d = 0.34-0.71; P < .01). Mean changes and effect sizes were larger for participants who reported declines compared with those who reported improvements. Small-to-medium ES were observed in patients who reported being "a little" worse (d = 0.31-0.56), and medium-to-large ES were observed in those who reported being "a lot" worse (d = 0.53-0.72). Hospitalized participants reported significant score increases, resulting in worsening of pain (d = 0.51), fatigue (d = 0.35), and depression (d = 0.57; all P < .01). Cancer recurrence and progression were associated with smaller increases in pain, fatigue, and sleep disturbance (d = 0.22-0.27).ConclusionsThe current results indicated that all 8 PROMIS measures were sensitive to patient-perceived worsening and improvement and to major clinical events. These findings will be able to inform the design and interpretation of future research studies and clinical initiatives administering PROMIS measures. Cancer 2017;123:327-335. © 2016 American Cancer Society
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Design and Optimization of a Micro-Aerial Vehicle
AIAA’s 2016 Design/Build/Fly Competition required the construction of two separate systems to complete distributive manufacturing missions. The team had to develop a production aircraft to carry a 1 kg payload and a manufacturing support aircraft which could carry the production aircraft internally. Aircraft designs were finalized using merit analyses and iterative design techniques to make quantitative decisions. The team selected a flying wing design for the production aircraft nested inside the wing of a conventional design manufacturing support aircraft as final configurations. The aircraft were manufactured and tested to ensure designs would complete mission requirements while maintaining the highest possible score by retaining minimal components and a low aircraft weight
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Proceedings from the 9th annual conference on the science of dissemination and implementation
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